Senior Fixed Voice Engineer: Ribbon & SBC Expert

Singapore Telecommunications; Sydney; Hybrid; AUD 180,000 - 240,000; Full time

Benefits offered by this job

Flexible work arrangements

Office on-site amenities

Employee discounts

Parental leave

Job summary

Optus is seeking a Technical Specialist, Fixed Voice to operate and enhance its Fixed Voice network infrastructure across Ribbon platforms. You will handle fault management, complex incident resolution, and proactive KPI monitoring in a hybrid work setup.

The role requires extensive hands-on experience with Ribbon platforms, SIP/TRUNKING, and ITIL processes, plus collaboration with NOC, Engineering and Service Management teams to modernise tooling and observability.

Qualifications

• 15+ years of wireline or Fixed Voice telecommunications experience across Ribbon or GENBAND platforms.
• Deep technical expertise in CS2000 (CS2K), C20 and SBC platforms including call control and trunk management.
• Strong knowledge of Ribbon Fixed Voice architectures including SIP trunking and SIP/TDM interworking.
• Advanced knowledge of SIP, SS7/ISUP, SIGTRAN, TDM E1/PRI, RTP/RTCP, G.711/G.729, DTMF, LNP/ENUM and IPv4/IPv6.
• Experience with Grafana, Kalix/OSIX, Wireshark, Ribbon EMS/RAMP, ServiceNow or similar ITSM tools and Unix/Linux CLI.
• Ability to interpret Fixed Voice KPIs like call completion, ASR, NER and MOS and act on trends.
• Experience in incident management, RCA, maintenance, upgrades, patching, MOP development and vendor TAC engagement.
• Bachelor’s degree in Telecommunications, Electronics, CS or equivalent; Ribbon certifications, CCNA/CCNP Voice and ITIL v4 Foundation preferred.
• Desirable observability, automation and safe AI-assisted operations knowledge.
• Strong ownership and clear communication under pressure with technical and non-technical stakeholders.

Responsibilities

• Operate and maintain Ribbon Fixed Voice nodes (DMS300, CS2000, C20, SBC, PSX, IN and sub-elements).
• Provide Level 2 fault management, incident resolution and technical support for outages and degradations per ITIL.
• Manage escalated faults across Enterprise and Wholesale environments.
• Perform structured fault diagnosis and root-cause analysis with corrective actions.
• Configure and manage C20 elements (GWC, SP2K, G9, MAS, SST, SSL/SESM/A2, CBM, CMT, IEMS, MG15K, NDM).
• Manage SIP trunking, routing and policy rules via Ribbon NMS; SIP/TDM interworking and service validation.
• Investigate voice faults using SIP, INAP, Diameter, RTP and C7/ISUP; use OSIX and Wireshark.
• Execute software upgrades, patch management and planned maintenance with testing, rollback and verification.
• Monitor Fixed Voice KPIs with Grafana and Kalix; address degradation trends affecting call completion, ASR, NER and MOS.
• Develop and maintain MOPs, implementation plans, risk assessments, change records and network docs.
• Collaborate with Network Operations, Engineering, Service Management, NOC, AI Ops, vendors to restore services and improve tooling.

Skills

Ribbon Fixed Voice

SIP/ISUP protocols

Grafana

Wireshark

ITIL incident mgmt

Education

Bachelor in Telecommunications

Ribbon certs

CCNA/CCNP Voice

ITIL v4 Foundation

Tools

Ribbon EMS/RAMP

ServiceNow

Unix/Linux

Kalix/OSIX

Job description

Optus is seeking a Technical Specialist, Fixed Voice to operate and enhance its Fixed Voice network infrastructure across Ribbon platforms. You will handle fault management, complex incident resolution, and proactive KPI monitoring in a hybrid work setup.

The role requires extensive hands-on experience with Ribbon platforms, SIP/TRUNKING, and ITIL processes, plus collaboration with NOC, Engineering and Service Management teams to modernise tooling and observability.